Twenty-Three
by DinoDina
Summary: Jack Harkness, as that was his name after so many years, was born with the number 23 on the back of his nondominant hand. He was human, mostly, so he had a soulmate. When they met, that soulmate would be twenty-three years old. It was simple. And Jack, despite his puzzlement over the necessity of soulmates, was excited. Janto Soulmate!AU oneshot.


_Soulmates were important to humans. Jack never understood why; there were so many people to love, so why settle for just one? But people did, and even as they moved out into the stars, the tradition of soulmates stayed the same—and it wasn't just a tradition._

 _Jack Harkness, as that was his name after so many years, was born with the number 23 on the back of his nondominant hand. He was human, mostly, so he had a soulmate. When they met, that soulmate would be twenty-three years old. It was simple. And Jack, despite his puzzlement over the necessity of soulmates, was excited._

 _Nothing happened when he turned twenty-three. But Jack didn't worry. His soulmate was the one who was going to be that age when they met._

 _He turned thirty-three and nothing happened._

 _By the time he turned forty-three, Jack knew that his life was leading nowhere._

 _He was by no means celibate. Nothing even close to that. He had relationships, he fell in love, and he lost everyone. By fifty-three, by sixty-three, by seventy-three, Jack stopped paying attention to the young people who wanted him. He was much too old, much too broken._

 _By eighty-three, Jack wanted happiness, and by ninety-thee, became hopeless._

Ninety-four lashes. Jack cries out, pulled out of his memories. Bleak as they are, they are better than what he has to face at the Master's hands.

He's a hundred and seventy-two years old.

He can barely comprehend the number, and if what the Doctor said is true, he has to face eternity like this.

Ninety-five lashes. The Master laughs; the guard that's beating Jack yells something; Jack wonders what number his soulmate has on his hand. How old will Jack be when they meet?

.oOo.

The paradox is over. Jack knows it, Martha knows it, the Doctor knows it, Martha's family knows it. No one else. The world spun, ended, and reset. Cities are standing where they were leveled. People are laughing where they died. The sun is shining.

Jack is a hundred and seventy-two years old. He's lived for a year longer than that, but that year didn't happen. _Why does he have to remember it?_

Jack plasters on a smile and ignores the Doctor's offer to travel. It's just a courtesy offer, he knows, because he's _wrong_. It's a bitter pill to swallow, but he does.

He bids the Doctor and Martha adieu and goes to find his team.

For all their anger, they're happy to have him back. All of them. Every single one. Jack doesn't remember the last time he's felt so loved, and it feels so _good_. He hugs Gwen and Tosh, and eventually Owen as well, and stammers his way through a conversation with Ianto.

Jack knows he's falling. Hard. He knows he's already halfway there, because there's no way for someone to be in Ianto's company for so long and not fall in love with him. Jack throws caution to the wind and talks to him, and Ianto listens.

Ianto may not be his soulmate—because the number on his hand is covered with medical tape, because the number is probably Lisa's and no one wants a reminder of a dead soulmate—but Jack's not curious. Not now. Not when they're so close and everything's going so well.

.oOo.

It's the middle of the night, and Jack and Ianto walk into the Hub, discarding their dirty clothes next to Owen's desk. There's no doubt that he's going to be pissed the next day, but it's technically his job to deal with potential contaminations.

Ianto laughs as Jack tugs him up the stairs to his office. "I need to go home," he says lightly, but Jack's been around long enough to know it's just a token protest.

"It's the middle of the night!" Jack tugs him closer; they're not yet in the office, but if he has his way, they will be. "You've been up for hours. You know it'll be irresponsible of me to let you drive."

"I need to get my clothes." Despite his words, Ianto leans against Jack. "I've gone through all my changes."

"You can borrow one of my shirts in the morning," Jack offers. "And I think you still have a pair of jeans here from that time we wanted to go out a few weeks ago."

It's an easy decision to make. "Yeah, alright."

It's the first night they spend together at the Hub, and it becomes a regular occurrence soon after that: Jack stays at Ianto's some nights, Ianto stays at the Hub, and occasionally they spend the night alone.

.oOo.

Jack's never hidden his hand. He may not fully believe in soulmates, but he's not against it or ashamed of it. No one asks him about it, anyway. They probably think it's a sensitive subject. And it is.

He has no idea who his soulmate is. Because of his lifespan, he doesn't know when they'll meet. Any person with whom he starts a relationship could be his soulmate; perhaps they met on the street or in the store.

Whoever his soulmate is, Jack's going to lose them. That's nothing he can lightly deal with. All he can do is be happy before they meet, be ecstatic when they're together, and continue to live when they're gone.

When he's with Ianto, they don't talk about soulmates. They don't talk about love. They talk about feelings, rarely, but they know where they stand with each other. Jack treats the number on his hand with nonchalance, and Ianto is still yet to show his, so the subject never comes up.

Until it _does_ come up, rather abruptly, on a rainy day in mid-July.

.oOo.

The previous night was so quiet, they spent it all at Ianto's flat, watching films while curled up on the sofa. At some point, they moved to the bedroom, because as Jack wakes up, he looks out the window at the cloudy mess outside.

No one ever said Cardiff boasted good weather. He's just happy that the Rift Predictor is letting them have the day off. He checks it again just in case—and Ianto would call him out on jinxing them, but better safe than sorry—and sees that the previous day's forecast looks true.

Jack turns over in bed to join Ianto in sleep—or just to watch him, but he hasn't decided that yet—and is just settling in when Ianto throws his hand over Jack's waist and moves closer.

It's an endearing gesture and it makes Jack's heart melt because Ianto always does it in the morning when he doesn't want to get up, but that's not what makes Jack's breath catch in his throat.

 _How does a kid deal with having '171' on his hand? How do his parents? How do his friends, his classmates, his teachers? How does anyone deal with knowing that his soulmate is so abnormal?_

Ianto was so careful about keeping his soulmate's age hidden. More careful than anyone Jack's ever met. And now—now, by a stupid coincidence, the _no-stick, no-slip, endurance guaranteed_ medical tape he uses to cover it slipped off.

Jack swallows. Once. Twice. It's too early in the morning to deal with anything like this, so Jack closes his eyes and turns away.

 _171_

 _171_

 _171_

 _How old is Ianto now? 24?_

But he can't stay so far for long.

Careful not to wake him, Jack takes Ianto's hand in his and lets himself be lulled into a vaguely relaxed state.

.oOo.

"Oh, god…"

The sound of Ianto's choked voice makes Jack open his eyes and he blinks up blearily at Ianto, who's already sitting.

"Ianto!"

"Oh, god…" Ianto stares at their linked hands, seemingly unable to say anything else. He looks up. "Jack?"

"Yeah?"

"How old are you?"

"A hundred and seventy-two years old." _Seventy-three_ , Jack says to himself, but as far as Ianto's concerned… well.

"Huh." Ianto nods to himself. He's looking back at their hands. "I thought so."

Jack blinks. "You what?"

"All your records are in the Archives," Ianto says, now looking at him. "As soon as I realized that you're older than you look, I dug a little deeper. It took me a bit of time, but…"

"You've figured it out." Jack's never doubted Ianto's intelligence, and probably never will. "And how long did you know? That it was me?"

"Not long. I've got to admit, until I found out you were immortal, my closest guess was that my soulmate would be a vampire." Ianto smiles and lies back down next to Jack, keeping their hands together. "I'm happy it's you."

 **(And Jack was happy, too, and they lived happily ever after :D)**


End file.
